The Los Angeles Police Commission voted Tuesday to require officers to try, whenever possible, to defuse tense encounters before firing their guns — a policy shift that marks a significant milestone in the board’s attempts to curb shootings by police.

The new rules formally incorporate a decades-old concept called “de-escalation” into the Los Angeles Police Department’s policy outlining how and when officers can use deadly force. As a result, officers can now be judged specifically on whether they did all they could to reduce tensions before resorting to their firearms.

Tuesday’s unanimous vote caps a 13-month effort by the Police Commission to revise the policy. Two sentences will be added to the department’s manual, the first of which tells officers they must try to de-escalate a situation — “whenever it is safe and reasonable to do so” — by taking more time to let it unfold, moving away from the person and trying to talk to him or her, and calling in other resources.Not everyone supported the new policy, however.

The American Civil Liberties Union sent the commission a letter before Tuesday’s meeting expressing concern the revisions did not go far enough to explicitly state that de-escalation would be considered when determining whether an officer’s use of force was reasonable. Without such language, the letter said, the ACLU urged commissioners to “refuse to accept the proposed revisions as complete.”

At Tuesday’s meeting, the commission’s inspector general said because commissioners can consider whether an officer’s actions before a shooting contributed to that shooting, the revisions do allow the panel to consider an officer’s de-escalation efforts — or lack of them — when deciding if a shooting was justified or not.

New training and directives from the LAPD reinforce the importance of de-escalation and the policy change, the inspector general, Alex Bustamante, added. LAPD officers expected to face more scrutiny over shootings with new rulesThe revamped policy is the latest in a series of changes the five-person Police Commission has made in hopes of reducing shootings by officers. For almost two years, the civilian panel has pushed LAPD brass for more training and to provide officers with less-lethal devices, as well as a stronger emphasis on avoiding deadly force whenever possible.

LAPD Officer Jin Oh displays video from a body camera. Some residents have raised privacy and civil liberties questions about the use of the devices. (Photo: Marcus Yam/ latimes.com)

The Los Angeles Police Commission voted Tuesday to approve a policy for equipping officers with body cameras, moving the LAPD a step closer to becoming the nation’s largest law enforcement agency to adopt the widespread use of the devices.

The 3-1 vote occurred after a sometimes-heated discussion over whether officers should be allowed to review video from the cameras before writing reports or giving statements to investigators following serious force incidents.

Civil libertarians opposed allowing officers to review the footage, though LAPD officials said investigators may prevent officers from looking at the video following force incidents that might result in a criminal investigation of the officers.